Texas Instruments UCC5619MWPTR, UCC5619MWP Datasheet

DESCRIPTION

UCC5619 provides 27 lines of active termination for a SCSI (Small Com­puter Systems Interface) parallel bus. The SCSI standard recommends ac­tive termination at both ends of the cable.

The UCC5619 is ideal for high performance 5V SCSI systems. During dis­connect the supply current is typically only 100µA, which makes the IC at­tractive for lower powered systems.

The UCC5619 is designed with a low channel capacitance of 2.5pF, which
eliminates effects on signal integrity from disconnected terminators at in­terim points on the bus.

The power amplifier output stage allows the UCC5619 to source full termi­nation current and sink active negation current when all termination lines
are actively negated.

The UCC5619, as with all Unitrode terminators, is completely hot pluggable
and appears as high impedance at the teminating channels with V

TRMPWR

= 0V or open.
Internal circuit trimming is utilized, first to trim the 110Ω impedance, and

then most importantly, to trim the output current as close to the maximum
SCSI-3 specification as possible, which maximizes noise margin in fast
SCSI operation.

Other features include thermal shutdown and current limit. This device is
offered in low thermal resistance versions of the industry standard 36 pin
wide body QSSOP (MWP) and 48 pin LQFP (FQP).

Consult SSOP-36 (MWP QSSOP-36) and FQP-48 Packaging Diagram for
exact dimensions.

UCC5619

27-Line SCSI Terminator With Reverse Disconnect

BLOCK DIAGRAM

FEATURES

• Complies with SCSI, SCSI-2, SCSI-3,
SPI and FAST-20 (Ultra) Standards

• 2.5pF Channel Capacitance during
Disconnect

• 100µA Supply Current in Disconnect
Mode

• 4V To 7V Operation

• 110 Termination

• Completely Meets SCSI Hot Plugging

• –900mA Sourcing Current for

Termination

• +500mA Sinking Current for Active
Negation

• Logic Command Disconnects all
Termination Lines

• Trimmed Impedance to 5%

• Current Limit and Thermal Shutdown

Protection

10/98

UDG-96108

Circuit Design Patented

2

UCC5619

ABSOLUTE MAXIMUM RATINGS

TRMPWR Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +7V

Signal Line Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . 0V to +7V

Regulator Output Current. . . . . . . . . . . . . . . . . . . . . . . . . . 1.5A

Storage Temperature . . . . . . . . . . . . . . . . . . . −65°C to +150°C

Junction Temperature. . . . . . . . . . . . . . . . . . .−55°C to +150°C

Lead Temperature (Soldering, 10 Sec.). . . . . . . . . . . . . +300°C

Currents are positive into, negative out of the specified termi­nal. Consult Packaging Section of Databook for thermal limita­tions and considerations of packages.

LINE5

LINE6

LINE7

LINE22

LINE21

LINE19

LINE20

REG

LINE9

LINE8

GND*

LINE26

LINE27

LINE23

LINE24

LINE25

GND*

GND* GND*

36

35

34

33

32

31

30

29

28

27

1

2

3

4

5

6

7

8

9

10 GND*

11

12

13

14

15

26

25

24

23

22

16

17

18

21

20

19

LINE12

LINE11

LINE10

DISCNCT

LINE13

LINE14

LINE1

LINE2

LINE17

LINE18

TRMPWR

GND*

LINE16

LINE15

LINE4

LINE3

* MWP package pins 8 - 10 and 26 - 28 serve as heatsink/
ground.

QSSOP-36 (Top View)
MWP Package

48

47

46

45

1

44

43

424140

393837

2
3
4

5
6
7

8

9
10
11
12

13

14

15

16

17

18

192021

22

23

24

36
35
34
33
32
31
30
29
28
27
26
25

LINE 22

LINE 5

LINE 6

LINE 7

LINE 8

HS/GND

N/C

LINE 24

LINE 9

HS/GND

HS/GND

REG

LINE 19

LINE 20

LINE 21

TRMPWR

HS/GND

LINE 17

LINE 18

LINE 16

LINE 4

LINE 15

LINE 2

LINE 3

N/C
LINE 12
LINE 13
LINE 14

HS/GND

LINE 27

LINE 26

LINE 25

DISCNCT1

HS/GND

LINE 10

N/C

LINE 11

HS/GND

HS/GND
HS/GND

LINE 23

HS/GND

HS/GND

LINE 1
HS/GNDHS/GND

HS/GND

N/C

CONNECTION DIAGRAM

LFQP-48 (Top View)
FQP Package

ELECTRICAL CHARACTERISTICS Unless otherwise stated, these specifications apply for T

A

= 0°C to 70°C,

TRMPWR = 4.75V, DISCNCT = 4.75V, TA= TJ.

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Supply Current Section

TRMPWR Supply Current All Termination Lines = Open 1 2 mA

All Termination Lines = 0.2V 630 650 mA

Power Down Mode DISCNCT

= 0V 100 200 µA

Output Section (Termination Lines)

Termination Impedance (Note 3) 104.5 110 115.5 Ω
Output High Voltage (Note 1) 2.6 2.8 3.0 V
Max Output Current V

LINE

= 0.2V, TJ= 25°C −22.1 −23.3 −24 mA

V

LINE

= 0.2V −20.7 −23.3 −24 mA

V

LINE

= 0.2V, TRMPWR = 4V, TJ= 25°C (Note 1) −21 −23 −24 mA

V

LINE

= 0.2V, TRMPWR = 4V (Note 1) −20 −23 −24 mA